Practice with Fischer Projections

Practice generating Fischer projections from line-angle drawings.

[@juliacarbery6101]

I have watched 6 other videos on how to draw Fischer projections today, and yours was the only one that made it click for me! Thank-you!!!

[@mevansthechemist]

Thanks for watching, Julia!

[@zoewaide6933]

I second this!

[@augustinematthew2055]

Same, all very confusing!

[@creamy0bear]

Best video on this I’ve seen. Thanks for doing some more interesting examples and explaining clearly and visually

[@kathysanchez9475]

Thank you so much!! 🧪⚛️ Watching from Ecuador. I'm a spanish speaker, but this explanation was better than in my language 🥹

[@msstephbiggs]

I hope God blesses you greatly for helping people like me! You deserve it!

[@mevansthechemist]

Thanks, Stephanie! You're too kind!

[@mainakbiswas323]

sir thank u for this great vdo.... my teacher teaches many short cut method for this[only to get the right ans] but i can not remember them because he didn't teach us how to look at the structures ,. now i don't have to mug up my head with tricks ....now i understand it...so i will not forget it.. thank u soooo much sir

[@sriharsha05]

really helpful , need such teachers all around for better understanding

[@Jon_Dang]

This made it very clear. THank you

[@mevansthechemist]

Thanks for watching!

[@NdizaMbambara]

Having my test on Sunday. Thank youuuuu, I was so stressed, atleast I have something down.

[@tiibrahim5714]

Really really helpful sir thank you

[@aqualux1214]

thank you so much!

[@aanesa3047]

very helpful, thank you!

[@wweuniverse9337]

sir thanks a lot for the video,I have a doubt sir if we just turn our top of head,the structure formed ,would it be wrong to say it as the enantiomer of original one??? I hope u will answer!!!

[@mevansthechemist]

Tushar Tapase Turning the top of your head to one of the other "ends" of the molecule wouldn't generate the enantiomer-only exchanging groups can do that! :-) Changing your viewpoint would only rotate the Fisher projection. Thanks for watching!

[@nyfinancestudent]

So for the second example, if I got the R/S configuration correct in the fischer projection, with CH3 on the vertical line, but the HS is on the top line and the Br is on the bottom line, would this be an accurate fischer projection compared to yours? This is the part that confuses me. In other words, I believe I am doing a 180 degree rotation.

[@yijun111]

👍👍👍👍👍👍👍👍👍

[@EleanorBrewer-f9p]

on part b, could you also have a version of the projection that has hs on the top left of the cross, and Br on the bottom right?

[@mevansthechemist]

Yes! Completely fine. A 180° rotation of a Fischer projection about an axis perpendicular to the screen or page generates an equivalent representation. What you put on top is sometimes a matter of personal preference. 😊

[@michielgifford]

just a question but in the last one doenst the OH group need to be on top becouse the first C in the name has to be on top in the fisher projection

[@mevansthechemist]

@@michielgifford Some might be more pedantic on this point than others, but to me, it doesn’t matter. 😁 That’s mostly a nomenclature thing.

[@ashutoshpanigrahy7326]

Thanks a lot!🙂🙃

[@bluejay2867]

How do you know where the hat is supposed to go? If you looked at it the opposite direction, wouldnt you perceive it differently?

[@mevansthechemist]

Sure, but this would lead to a different-looking but equivalent (equally correct) zig-zag representation. The key is to choose an orientation for the "head" and apply it consistently!

[@ParadiseKuna]

thank you for this

[@angellin6343]

how did you decide where to draw the eyeball?

[@mevansthechemist]

To some extent, this is based on convention...it's important to orient the eye so that horizontal bonds point toward it and vertical bonds away from it. However, what you put at the top and bottom is often up to you. In Fischer projections of monosaccharides, the carbonyl/hemiacetal carbon is usually placed on top by convention.

[@vikramkc2219]

Nice video

[@spicydiarrhea5662]

Thanks! Nice rectum at the center of your pfp👍♥

[@Samanvi356]

Sir. Last examples is difficult to me Do u have another easy trick

[@Andrewhastings247]

Those Ps r hats?

[@justsomegirlwithoutamustac5837]

How do we know where to draw the implied hydrogen?

[@therealporphyrio]

You’re cooked 💀

[@temimkedir9742]

Can I ask aqution about fisher projection?

[@mevansthechemist]

Ask away!

[@spicydiarrhea5662]

yes Temim Kefir, you have my permission.

[@tomokochii]

this is so confusing goooood

[@biolaude]

i still dont understand :(

[@temimkedir9742]

I want to appretioate you

[@郭婷瑜-c5n]

C shape! Nobody mentioned 🥲 I was confused about how to draw the fisher projection of double chiral center. If the carbon backbone isn’t in c shape, it does not make sense so I had no idea how to draw the projection😩

[@mevansthechemist]

Yep-people tend to gloss over the visualization and conformational issues with Fischer projections. It gets tricky!